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Learning Learning about weather (soundings, H5, etc..)

SD

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#32
Its really convective energy at different levels and points for layman terms. For instance SBcape stands for surface based cape which is the convective energy starting at ground level. DCape is downdraft cape which us used to determine the strength of downdrafts. Presence of MLCape with low SBcape tells you that there is a cap and any convection at that point would be elevated.

I look at SBcape first and then on most soundings you will see 0-3km Cape which I look at next.
Setting spring severe aside when looking for summer tstorms would you look more toward MLCAPE vs SB? I've noticed many times in the summer when we get capped our SB will be in the 2000+ range but ml is much less and we have a ton of flat cumulus

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Arcc

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#33
Setting spring severe aside when looking for summer tstorms would you look more toward MLCAPE vs SB? I've noticed many times in the summer when we get capped our SB will be in the 2000+ range but ml is much less and we have a ton of flat cumulus

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I think I would look more at SBcape, but Im embarressed to say I only look at soundings when there is severe weather possible. Its like when my wife asks me what the weather will be this week when I havent looked at it because Im focused on something a week away. She always gets me with the comment that I should know because im watching the weather enough.:oops:
 
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#34
Can somebody help breakdown what made april 27th 2011, so bad in terms of meteorological factors? Because ive heard james spann say something like for that day 63 or 64 things on a checklist of 67 for severe weather were in place. Im just curious to what made is SO bad. Living here in it and being around when it happened ive always been traumatized by how the day felt and how many horrible things happened that day. It was what triggered me to want to know more about the weather and being aware of it. But thanks in advance if anyone wants to help or explain the details. Ive looked at weather soundings from that day and dont understand what factors made it so bad. Other than an outflow boundary sitting on top of birmingham and dryline approaching during peak daytime heating. Along with high helicity Screenshot_20190317-230541_Samsung Internet.jpg
 
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#35
Also another thing i read about that day was there was controlled forest burning in south america which the smoke travelled up into Mississippi and alabama which may have aided in the storms any ideas on how that wouldve effected things?
 

Myfrotho704_

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#36
Also another thing i read about that day was there was controlled forest burning in south america which the smoke travelled up into Mississippi and alabama which may have aided in the storms any ideas on how that wouldve effected things?
Here’s the best I can give, perfect setup with a really powerful negativily tilted trough, lots of sfc moisture, then Capping developed after morning MCS came through which allowed good CAPE (3000+) which argues for extreme updraft development once it broke, also had a EML present, had a strong low pressure system in a good place for severe wx (Kentucky), steep lapses, high Equilibrium layer, ageostrophic flow which would end up aided in extremely violent rotating storms and extreme helicity, supercells found this environment and flourished, they had the environment to there self, combination of extreme CAPE and helicity is extremely dangerous, I think what didn’t help was the fact that the morning storms gave some people a mindset that it was over or it wouldn’t be bad later, as you said tho boundaries had a significant effect, there so underrated in outbreaks, they can aid in some of the most violent tornadoes
 

Myfrotho704_

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#37
Interesting with that setup in 2011, the tornadoes you either had were large stovepipes with side vortices (Tuscaloosa), large wedge tornadoes with the Mesos scraping the ground (Phil Campbell/Hackleburg), or had tornadoes that were very tilted (Cullman)
 
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#38
Interesting with that setup in 2011, the tornadoes you either had were large stovepipes with side vortices (Tuscaloosa), large wedge tornadoes with the Mesos scraping the ground (Phil Campbell/Hackleburg), or had tornadoes that were very tilted (Cullman)
, im guessing we got lucky then last storm system that the low wasn't closer too us. More shear and a stronger LLJ would've aided in more instability. Provided the discreet mode of the supercells.
 
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#39
, im guessing we got lucky then last storm system that the low wasn't closer too us. More shear and a stronger LLJ would've aided in more instability. Provided the discreet mode of the supercells.
The veterans day 2002 tornado outbreak was the closest analog event for that day which is intresting because it produced long track but less intensity tornado tracks on a Fall day.
 

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#40
Can somebody help breakdown what made april 27th 2011, so bad in terms of meteorological factors? Because ive heard james spann say something like for that day 63 or 64 things on a checklist of 67 for severe weather were in place. Im just curious to what made is SO bad. Living here in it and being around when it happened ive always been traumatized by how the day felt and how many horrible things happened that day. It was what triggered me to want to know more about the weather and being aware of it. But thanks in advance if anyone wants to help or explain the details. Ive looked at weather soundings from that day and dont understand what factors made it so bad. Other than an outflow boundary sitting on top of birmingham and dryline approaching during peak daytime heating. Along with high helicity View attachment 17846
In addition to what Fro said, the day had perfect conditions for discrete supercells. The trough was negatively tilted, but it was broad based and allowed the forcing to be more spread out and allowed the upper level shear to hit the boundary at a sharp angle as you can see by the westerly winds at 500mb.

Another factor was the insanely deep moisture. Normally in a event with this much wind shear and sunshine, the drier air mixes down and drops dewpoints. That has turned many tornado outbreaks into lots of non-tornado producing supercells.

The last big thing was the rain cooled boundary/psuedo warm front that formed across north AL/MS/GA. This backed winds and increased helicity to 800-1000. No wonder this area sparked three tornadoes that are amoung the strongest recorded but many other deadly tornadoes. The day would have been historic without it, but that area topped it off.
 

Myfrotho704_

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#41
So what do u look for if u want hail on these soundings and how do u know what type of hail or size it supports
Perfect hail sounding, note such large CAPE in the hail growth zone (-10c to -30), dry air aloft and this sounding pretty much explains the rest, shear can help out by sustaining hail in a updraft allowing the hail to grow in size, ima just put this here since this is the learning thread and this thread is not used much, lol, a mod can delete the one I put in the March thread
2A1C829B-1FE2-438E-BE13-3AB91FB6027C.jpeg
 

Arcc

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#42
Perfect hail sounding, note such large CAPE in the hail growth zone (-10c to -30), dry air aloft and this sounding pretty much explains the rest, shear can help out by sustaining hail in a updraft allowing the hail to grow in size, ima just put this here since this is the learning thread and this thread is not used much, lol, a mod can delete the one I put in the March thread
View attachment 17940
To add to this, my rule if thumb for large hail to to see where the wetbulb zero height is. When I see that WBZ at or below 700mb along with strong instability,lapse rates and strongly negative LI, and decent bulk shear; large hail is very favored.
 

Myfrotho704_

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#43
There’s fixed vs effective
Effective Layer uses multiple ingredients, uses effective bulk wind difference or EBWD for short, effective storm-relative helicity or ESRH for short, 100mb mean parcel COnvective available potential energy or mlCAPE), 100mb mean parcel Convective inhibitation, mlCIN) also 100mb mean parcel Lifted condensation level height, mlLCL for short
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Fixed Layer uses A bit different ingredients, includes 0-6 km bulk wind difference, or 6BWD for short, 0-1 km storm-relative helicity, SRH1), surface based Convective available potential energy, sbCAPE), surface parcel Convective inhibitation, sbCIN), and surface parcel Lifted condensation level height, sbLCL) I’ma put this here, because why not
 
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